Objectives: Racial-ethnic differences in physical/mental health are well documented as being associated with disparities; however, emerging conceptual models increasingly suggest that group differences in social functioning and organization contribute to these relationships. There is little work examining whether racial-ethnic groups respond similarly to classic measures of social networks and perceived support and whether there are significant between-groups differences on these measures.Method: A multisite, cross-sectional study of 2,793 non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic participants was conducted using common measures of social networks and perceived support. A confirmatory factor analytic model was used to test for the invariance of factor covariance and mean structures in a three latent constructs model including social network, social provisions, and interpersonal support. Between-group differences in structural and functional support were assessed.Results: We established measurement invariance of the latent representations of these measures suggesting that racial-ethnic groups responded comparably. In direct comparisons, Hispanics and NHWs demonstrated similar levels of network structure and support. In contrast, NHWs reported support advantages on a majority of measures compared with NHBs.Conclusions: Findings support the use of these measures across groups and provide initial support for potential differences in this hypothesized mediator of racial-ethnic health disparities. (PsycInfo Database Record (c) 2020 APA, all rights reserved). [ABSTRACT FROM AUTHOR]